This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The malaria parasite, Plasmodium falciparum, is believed to cause binding of infected erythrocytes to the placenta in pregnant women through interactions of certain domains of the VAR2CSA protein with cell-surface glycosaminoglycans, specifically chondroitin 4-sulfate (C4S). DBL3X domain has been predicted to play key roles in the binding of VAR2CSA to C4S. Dr Gowda's laboratory has provided plasmids and protocols for expressing the DBLX3 domain of the protein for the purpose of testing and characterizing these hypothesized interactions. Personnel at the Resource are producing 13C-labeled forms of specific C4S oligomers that can be used in assessing the specificity of interactions and, and will express appropriately labeled forms of the protein. The NMR methods that allow use of 13C chemical shift anisotropy offsets in aligned samples to return geometry information on the complexes stem from previous Resource supported work on residual dipolar couplings (RDCs).